I personally feel the more testing? The better. You will always find some contradictions between tests, that some materials on the serum test may not test well on the other tests because I guess they are testing for different kinds of compatiblity (energetic/immune etc) but usually there will be a few materials that turn out ok on most, or all tests and then you got a pretty darned good bet they'll probably be the best suited for you. Personally I feel somewhat confused by them all, not sure exactly what each tests for, but probably best to just go with what materials come out tops.

I use the serum test as the foundation to work from. So I go from there. You can narrow it down further by subsequent tests like the one Sunshine has mentioned, EAV testing (voll testing) etc if you want to do that.